一种快速选配机床挂轮的方法

通过计算器简单、快速的计算，可快速选配机床挂轮。     

圆柱齿轮齿厚圆柱测量M值及公法线长度的计算机算法

介绍一种适合各种渐开线圆柱齿轮齿厚圆柱测量M值及公法线长度的计算程序。根据圆柱齿轮测量的相关计算公式,采用数值逼近法编程近似计算出测量尺寸,计算精度可根 据需要选取,操作简单、快捷,结果准确,大大简化了非标齿轮齿厚圆柱测量M值及公法线长度复杂的手工计算,是非标齿轮制造检测过程中非常实用的计算程序。     

摩托车后轮轴断裂分析

采用光学显微镜、扫描电镜、硬度测试等方法，对摩托车后轮轴断裂件进行了分析。结果表明，后轮轴断裂属于脆性断裂，因在其各部位所受载荷不同，呈不同的断裂形式；碳氮共渗工艺选择不当，共渗层过深，表面出现壳状碳氮化合物、内氧化等缺陷组织是造成其断裂的主要原因。     

减速机的预知性故障分析及处理

着重从 2个方面 ,运用监测系统检测减速机振动的数据进行分析 ,结合实际经验现场观察减速机使用状况 ,来分析预知故障 ,并及时处理     

艉轴端面密封副摩擦学性能研究

对舰用艉轴密封副材料进行了筛选和研究，结果表明在不锈钢基体上热喷熔镍基合金不仅经济性好，而且其与YG8组成的摩擦副具有极其优异的摩擦学性能，优于硬质合金摩擦副。解决了因海水中泥沙含量大而导致机械密封环寿命过短的问题。     

CaO-Al2O3 渣系对 20CrMoH 齿轮钢中总氧和硫的影响

研究分析了CaO-Al2O3精炼渣系对140 t LD Al直接脱氧齿轮钢T[O]和[S]的影响.结果表明,控制钢包渣中CaO/Al2O3为2.5,可使T[O]降低到0.001 3%;当渣中CaF2为5%,CaO/Al2O3为2～3时,能够增强炉渣吸收氧化物夹杂的能力;当(SiO2)增至6%～9%时,其含量变化对炉渣脱硫性能影响不大.当(siO2)为5%～10%时,较佳的精炼渣成分为(%):60～65 CaO、20～30 Al2O3、5～10 MgO、5 CaF2.     

中国高速铁路几个重要零件的精锻成形

介绍了为适应高铁对轨道及列车提出更高安全性、可靠性和舒适性要求,当前国内高铁某些重要零件采用的精密锻造成形工艺、无切削全纤维模锻成形工艺及一次加热模锻成形自动化操作工艺;概述了高铁车轮锻压技术研究进展和高铁车轴的径向锻造工艺和楔形模横轧工艺。此外,文章还介绍了高速列车制动盘锻压技术的研究现状。     

An acoustic–structural interaction modelling for the evaluation of a gearbox-radiated noise

Gearbox power transmissions are widely used in the automotive industry. They have a complex vibro-acoustic behaviour that is influenced by the various acoustic–structural interaction mechanisms. This paper concentrates on modelling these systems using a three-dimensional finite-element (FE) approach for the structure combined with a Rayleigh integral (RI) method for the acoustic radiation process. A modal analysis method is used to evaluate the elasto-acoustic modal characteristics for the coupled system. Effect of the fluid inside the gearbox on the vibration response is discussed. The combined use of this FE/RI model enables evaluation of the acoustic response. A case study of a simplified gearbox internally excited with gear mesh stiffness fluctuation is presented. Vibratory analysis allows concluding that the vibro-acoustic coupling between elastic housing, air-cavity and free acoustic field have not to be neglected.     

Dynamic analysis of involute spur gears with asymmetric teeth

New gear designs are needed because of the increasing performance requirements, such as high load capacity, high endurance, low cost, long life, and high speed. In some applications, such as in wind turbines, the gears experience only uni-directional loading. In these instances, the geometry of the drive side does not have to be symmetric to the coast side. This allows for the designing of gears with asymmetric teeth. In previous studies related to bending stress and load capacity, high performance has been achieved for gears with asymmetric teeth. These gears provide flexibility to designers due to their non-standard design. If they are correctly designed, they can make important contributions to the improvement of designs in aerospace industry, automobile industry, and wind turbine industry. At high operation speeds, there is always a concern of dynamic loads and vibrations of equipment. Therefore, there is a need to fully understand the dynamic behavior of gears with asymmetric teeth. Thus, the primary objective of this paper is to use dynamic analysis to compare conventional spur gears with symmetric teeth and spur gears with asymmetric teeth. The secondary objective is to optimize the asymmetric tooth design in order to minimize dynamic loads. This study offers preliminary results to designers for understanding dynamic behavior of spur gears with asymmetric teeth. For this study, a dynamic model was developed, using MATLAB, and used for the prediction of the instantaneous dynamic loads of spur gears with symmetric and asymmetric teeth. Furthermore, a 2-D three-tooth model was developed for finite element analysis. Fast Fourier transform was used for the frequency analysis of the static transmission errors. It is shown that generally, the dynamic factor, for spur gears with asymmetric teeth, increases with increasing pressure angles on the drive side. For asymmetric teeth, increasing the addendum leads to a significant decrease in the dynamic factor. The static transmission error, at the center of the single tooth contact zone, decreases with increasing pressure angle. The first two harmonics slightly increase with increasing pressure angle. It is further shown that the amplitudes of harmonics of the static transmission errors are significantly reduced when asymmetric teeth with long addendum providing high gear contact ratio close to 2.0 are used.     

ANALYSIS OF TRANSMISSION CHARACTERISTICS OF COSINE GEAR DRIVE

Based on the mathematical model of a novel cosine gear drive, a few characteristics, such as the contact ratio, the sliding coefficient, and the contact and bending stresses, of this drive are analyzed. A comparison study of these characteristics with the involute gear drive is also carried out. The influences of design parameters including the number of teeth and the pressure angle on the contact and bending stresses are studied. The following conclusions are achieved： the contact ratio of the cosine gear drive is about 1.2 to 1.3, which is reduced by about 20% in comparison with that of the involute gear drive. The sliding coefficient of the cosine gear drive is smaller than that of the involute gear drive. The contact and bending stresses of the cosine gear drive are lower than those of the involute gear drive. The contact and bending stresses decrease with the growth of the number of teeth and the pressure angle.